//执行循序 先初始化基类属性然后调用初始化constructor方法再初始化子类属性调用初始化constructor方法
class Base3 {
  name = 'base'
  constructor() {
    console.log('My name is' + this.name);
  }
}

class Derived3 extends Base3 {
  name = 'derived'
  constructor() {
    super()
    console.log(this.name);
  }
}

const d3 = new Derived3()